Fig. 7
TGF-β1 is essential for MSCs induced CRPC cells autophagy and docetaxel chemoresistance. a MSCs (1 × 106) growing to 50–60% confluence in 10 cm petri dishes were transfected with TGFβ1-targeting siRNA or their corresponding non-targeting siRNA using lentiviral vectors for 48 h. PC3 cells were transfected with GFP-tagged LC3. Images were taken under a fluorescence microscope. b PC3 cells (2 × 105/well) were cocultured with MSCs in a 6-well plate with an existence of DTX for 48 h. CCK8 was employed to examine the proliferation of PC3 cells. c Real-time PCR was employed to examine the PCNA expression level of PC3 cells. Results were reported as ratio to control group. d PI/Annexin V-FITC assay was used to measure apoptotic PC3 cells by flow cytometry. e PC3 cells and MSCs were prepared either as single-cell type suspensions (1 × 106 PC3 cells in 200 μL PBS) or a mix of cells (1 × 106 PC3 cells and 2 × 105 MSCssi-TGF-β1 in 200 μL PBS). PC3 cells (alone or mixed with MSCssi-TGF-β1) were subcutaneously administrated in the armpit area of nude mice with DTX administration. PC3 tumor volume was observed to evaluate the effect of TGF-β1 on tumor growth after DTX administration. f On 27 day after implantation, the animals were sacrificed. Tumor tissues were removed from mice and tumor weights were measured. *P < 0.05; **P < 0.01